Oh to be a fly on the wall at Team Obama's headquarters. Surely their internal polling must be showing similar trends. From USA Today:

In the new poll, taken Friday through Sunday, McCain leads Obama by 54%-44% among those seen as most likely to vote. The survey of 1,022 adults, including 959 registered voters, has a margin of error of +/-- 3 points for both samples.

Here's something worth noting: the article led with the poll of registered voters that has McCain up 50% - 46%. The paragraph I quoted above was buried at the end of the article.

I'm not challenging the poll (I hope it's true) but I would beware the media intentionally inflating the GOP post convention bounce in the coming week(s). As the bounce will ultimately decline thus giving the media the opportunity to pronounce the end of Palinmania and a new Obama surge.

"Quick! There's not a second to lose! Start leaking the adultery story! Call all the journalists you know! Muffy! Get me the New York Times on the horn! Bruce! Get me the National Enquirer! We're losing ground here! Everybody, see Nkwama for today's denial sheet! Hop hop, people!"

I guess you must have outsourced your statistical advice to the NYT or something. We poll millions, but that's called election day.

Otherwise a sample starting roughly at 600 people gives you a pretty good idea of what you are trying to estimate. I'm going from memory (not having done this for a few years) but you roughly get +/- 5% at 95% confidence with sample size of 600.

My guess is you can get up to 99% with +/-5 or 95% with +/2 or so as you increase the sample size to over 2000. After that you really see hugely dimishing returns.

A sample size of millions would just be rediculous. Would you as "former executive in marketing research" actually pay 1000 times the cost necessaery (2 million samples vs 2000 sample - what is a large sample when the means are between 0.3 and 0,7) to get information that is only marginally better? LOL, only if you work for the NYT I guess.

Ed and Mitch at Hot Air interviewed Doug, a volunteer driver who worked for the Republican National Convention Committee in St. Paul. The summary ...

-- According to Doug, MS-NBC apparently took no chances on questions from the crowd. Rather than get caught with a question that might make Republicans look good, their producer pre-screened questioners, and Chris Matthews pretended it was random.
-- Republicans were good tippers. MS-NBC stiffed the drivers.
-- Media people talked in the cars about how effective the Republican convention turned out to be, while publicly saying something else entirely.

"Just remember it is a poll of 1,000 people and I've been an executive in market research and polling (now retired).

This is a tiny sample;..."

Diane, the size of the sample is effectively irrelevant: instead, the purpose of all such samples is to capture the makeup of the larger population. Polling companies go to enormous lengths to try and ensure that their samples are representative. As a former exectutive in market research I'd have thought you'd know this.